Abstract: The types and contents of minerals in the soft soil is a fundamental issue in investigating the physical and mechanical properties of the soil, which can be obtained by conducting the micro experiments. In this study, the soft soil in Shanghai is taken as an example, and the element contents in the soil are obtained using the X-ray fluorescence (XRF) spectrum. The types of the crystalline minerals are obtained by combining with the X-ray diffraction (XRD) and XRF analyses. The mineral contents are thereafter obtained according to the element contents and mineral types. Distributions of different mineral contents in the soft soil are further analyzed. The results show that the elements of the soft soil in Shanghai are oxygen, silicon, aluminum, ferrum, carbon, potassium, magnesium, calcium and sodium. In all of the soil layers, the maximum content of the elements is oxygen followed by silicon, and the included minerals are quartz, albite, calcite, dominate, illite, chamosite and biotite with the quartz content ranging from 35.8% to 50.8% and others less than 21%. In the cohesive soils, the percentage of aluminum and the contents of illite and chamosite are greater than others included in the sandy or silty soils with a contrary way for the contents of albite and calcite. The results presented herein may provide references in investigating the physical and mechanical properties of the soils in a micro level.